Video is the technology of electronically capturing, recording, processing, storing, transmitting, and reconstructing a sequence of still images representing scenes in motion. The still images are provided to a viewer at a constant rate. The constant rate refreshes the still images faster than the human eye can detect, resulting in the appearance of fluid motion. The constant rate of refreshing the still images is known as a frame rate.
Frame rates may vary from application to application for many different reasons. For example, camera equipment used to capture the still images may be limited to one or a particular number of available frame rates. As another example, certain videos may offer a more pleasing appearance when provided at particular frame rates. For example, film and video makers often use a 24 hertz (frames-per-second) frame rate to achieve an on-screen look that matches native film. As a further example, certain viewing devices (e.g., televisions) are configured to operate at one of a select number of frame rates (e.g., PAL and SECAM televisions operate at a standard rate of 50 hertz, NTSC televisions operate at a standard rate of 60 hertz, and certain experimental viewers operate at a rate of 72 hertz).
While video may be captured and stored at any of a number of frame rates, it may be desirable to provide or view that video at a different frame rate from which it was captured or stored. Frame rate conversion provides a mechanism for changing frame rates from a frame rate at which the video is stored to a frame rate desired for viewing. Video can be converted to a higher frame rate using an upconversion operation, where one or more additional frames are interpolated between the existing frames of a source video.